flex wrap bootstrap
<div class="d-flex flex-wrap">...</div>
alighn right boostrap 4
<div class="float-left">Float left on all viewport sizes</div><br>
<div class="float-right">Float right on all viewport sizes</div><br>
<div class="float-none">Don't float on all viewport sizes</div>
bootstrap justify-content-center for md
<div class="row justify-content-md-center"></div>
bootstrap display flex
<div class="d-flex">I'm a flexbox container!</div>